Molded fiber materials and methods and apparatus for making the same

Abstract

A raw material including a mixture of a natural fiber and a thermoplastic fiber is supplied to a surface of a rotating rotary body. The natural and thermoplastic fibers are scattered toward a carrying surface of a conveyor belt by the rotational force of the rotary body. An air blower may direct pressurized air to the scattered raw material in order to further effect separation of the natural and thermoplastic fibers. Consequently, the natural fibers and the thermoplastic fibers are deposited such that the relative concentration of the natural fibers and the thermoplastic fibers gradually and seamlessly changes or varies across the thickness of depth of the resulting molded fiber material.

Description

BACKGROUND OF THE INVENTION[0001]1. Field of the Invention[0002]The present invention relates to molded fiber materials that may be utilized, e.g., as a trim material, such as door trim for automobiles, a construction material, such as wall material for houses, and furniture. The present invention further relates to methods and apparatus for manufacturing such molded fiber materials.[0003]2. Description of the Related Art[0004]Known fiber laminates (graded mats) provide variations in concentration of a natural fiber and a thermoplastic fiber across the thickness or depth of the fiber laminate by adhering a plurality of discrete layers. As shown in FIG. 9, a known fiber laminate 100 has been manufactured by adhering a plurality of layers 101-103 that were separately and individually manufactured in advance. Each layer 101-103 has a substantially uniform concentration or mixture of the natural and thermoplastic fibers, although the concentration or mixture of the natural and thermopla...

AI Technical Summary

Benefits of technology

The present invention provides techniques for manufacturing molded fibrous materials with seamless interfaces between layers and increased strength as compared to known fiber laminates. The techniques involve mixing natural fibers and thermoplastic fibers in a raw material, which is then supplied to a rotary body for scattering and deposition. The concentration of each fiber type changes gradually across the thickness of the material, resulting in a seamless product with high natural fiber content on the first and second surfaces and high thermoplastic fiber content in the interior. The invention also provides methods for preparing the molded fibrous materials and apparatus for making them.

Problems solved by technology

However, the known fiber laminate 100 is disadvantageous, because it is necessary to separately manufacture each of the layers 101-103 and each respective layer 101-103 requires a different concentration and a separate manufacturing process.

Therefore, known fiber laminate manufacturing processes require many steps, thereby complicating the production process and reducing productivity.

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